Polder to De-polder: an Innovative Sediment Management in Tidal Basin in the Southwestern Bangladesh

Abstract

The southwest region of Bangladesh has been affected by the perennial waterlogging due to excessive riverbed siltation. An introduction of tidal basin concept by temporary de-poldering at some places has significantly protected the circumstances. The paper looks at the historical practice of sediment management, the evolution of polder and depolder, and investigates some technical aspects evolving the processes. The temporary restoration of tidal flooding by de-poldering has started from age-old practice, proves technically one of the effective methods of sustainable water/sediment management in the tide-dominated river system. Although an embankment along the coast is required, sediment management is also essential for sustainability. It is the example of building with nature and a resilient measure for water-logging, drainage congestion, and river siltation.